Automobile signaling device



Dec. 26, 1944. J. JOYCE AUTOMOBILE SIGNALING DEVICE Filed Feb. 26, 19422 Sheets-Sheet 1 /4 TM ll AUTOMOBILE S IGNALING DEVI CE Filed Feb. 26.1942 2 Sheets-Sheet 2 Patented Dec. 26, 1944 UNITED s'rA' 'Es PATENTOFFICE 1 Claim.

and, as herein illustrated, relates more particularly to stop andwarning lights for use on motor driven vehicles.

Stop lights for use in .automobiles of the type wherein a signal lightis energized upon application of the brake of the vehicle are in commonuse. Such a light is effective to warn the operator of the following carthat the leading car is about to stop. Such lights, however, arenormally unenergized and are lighted only when the operator appliespressure to the brake to slow down or stop the car. There is no meansfor determining whether such a light is operative and the operators offollowing cars have to take it for granted that this type of stop lightalthough not lighted is in good working order. Thus, if the light isdefective and it becomes necessary for the operator of the vehicle tostop suddenly, the operator of the following car has no warning andhence my collide with the leading car. Stop lights which are energizedonly when the brake of the vehicle is applied, under most conditions ofuse, are eifective as signaling devices but when they are defective failto give warning to opera-" of the leading car at the instant suchchanges of speed take place.

One object of the invention, therefore, is to provide a signal devicefor motor vehicles which will certainly and under all conditions advisethe operator of the following car as to changes of speed of the leadingmotor vehicle at the time that the change of speed takes place. To thisend, and in accordance with one feature of the invention, a signal lightis provided which at normal operating speeds of the motor vehicle willwill appear to glow steadily. Thus, with a fast moving vehicle, a steadylight will be showing but when the speed of the vehicle drops below apredetermined rate of speed as,, for illustration, twenty miles perhour, the light visibly will be lighted and extinguished periodicallyand at slower intervals as the speed of the motor vehicle The presentinvention relates to signal lights tor vehicle that the leading motorvehicle is slowing down and is about to stop. -If the engine is idlingafter the motor vehicle is stopped, the light, with one adaptation ofthe invention will go on and of! at a low frequency, but if the engineis stopped, the light will be out. If the motor vehicle starts from astop the frequency of the light will steadily increase as the engine andvehicle pick up speed and when the speed of the car exceeds somepredetermined rate of speed, as for instance the above noted twentymiles per hour, the light will appear to be steady and continuous. Thus,the operator of the following motor vehicle is enabled not only todetermine whether the leading motor vehicle is about to stop but is alsoenabled to determine when the leading motor vehicle is accelerated. Thefrequency of illumination also gives the viewer an indication of thespeed of the vehicle.

Another object of the invention is to provide a signaling device whichis automatically controlled and which will be effective to warn theoperator oi the following motor vehicle of changes of speed of theleading motor vehicle at the instant that such changes of speed aremade.

Another object of the invention is to improve generally upon theconstruction and operation of signaling devices for motor vehicles.

With'the above and other objects and features Fig. 4 is a wiring diagramof the modification shown in Fig. 3;

Fig. 5 is a rear view illustrating the signaling device of Figs. 1through 4 with a portion of the covering broken away to illustrate thecontact structure.

Fig. 6 is a view taken along the line 6--6 of Fig. 5;

Fig. '1 is a view in cross-section taken along the line 1-1 of Fig. 6;

Fig. 8 is aview of a modified form of neon tube:

Fig. 9 is a view in section taken along the line 9-9 of Fig. 8;

Fig. 10 is a view in section taken along the line low-l0 of F18. 8;

decreases, thus informing the operator of the mo- Fig. 11 is a view insection illustrating the neon shaft 56, which is grounded and I2 whichis provided with the usual type of cutout I 4 which operatesautomatically to connect the generator electrically to a storage batteryl8 when sufficient energy is produced by the gener-- ator to move thecontact of the cut-out into closed position. The'generator I2 is alsoprovided with a circuit interrupter -l1 pertinent to the presentinvention and which is mounted on the rear end face of the generator I2and insulated therefrom. The interrupter I1 is electrically connected bya conductor I8 to one of the terminals IQ of the primary winding of atransformer 20 mounted in a casing 22, fixed in any suitable manner to apart as a rear. wall 24 of the motor vehicle. Another conductor 26 isalso provided which leads from the other terminal 2| of the primarywinding of the transformer 20 and is electrically connected to thecutout l4 as will later be described.

Referring now to Fig. 2 of the drawings, it will be noted that thegenerator I2 is provided with a lead 28 which electrically connects aterminal or brush l2a of the generator with a current winding 21 and avoltage winding 29 of the magnet 30 of the cut-out l4. When the voltagewinding 29 is sufficiently energized, a contact carrying bell cranklever 32 is moved in a counter-clockwise direction to move a contact 34on the bell crank 32 into engagement with a stationary contact 36, thusclosing the circuit between the generator I! and the storage battery I6through the conductor 31 to one terminal of the battery. The otherterminal is grounded as is a second terminal or brush H?) of thegenerator so that the circuit is complete. The conductor 26 is connectedat one end to the bell crank lever 32 and at its other end, as abovestated, to one of the terminals of the primary coil of the transformer20. A fuse 38 is placed in the circuit to protect the device againstshort-circuit. One end of the conductor l8, as above stated, isconnected to the other terminal of the primary transformer 20 and at itsother end is electrically connected to the interrupter l1 whichcompletes the circuit through the primary coil of the transformer 20.

The interrupter I1, as illustrated in Fig. 13 of the drawings, comprisesan insulating block 40 fixed by screws or other suitable means to theend cap of the generator 12 or to any convenient support.

Brackets 42 having substantially horizontally extending lower arms arefixed to the insulating block 40 by machine screws or other suitablefastenings. The brackets 42 support a metallic cup 44 formed of steel orother suitable material. Said cup contains mercury about to the level48,

the cup above the mercury containing oil or other suitablenon-conducting and oxidization-preventing fluid. The cup 44 is providedwith a cover member 48 formed of hard rubber or other suitableinsulating material and is provided with an opening arranged to receivea vertically reciproeating metal plunger 80 which at its upper end ispivotally connected to a crank rod l2, which. in turn at its upper end,is secured by a pin It to the shaft 56 of the generator l2 eccentricailyof the axis thereof. The plunger 58 and the link 52 are formed of anysuitable metal, preferably steel, and are electrically conducting sothat the thereby electrically connected withthe terminal l2b of thegenerator can be intermittently electrically connected to the mercury inthe cup 44. Thus, when the shaft 56 of the generator I2 is rotated. thecircuit between the mercury and the pllmger l2 is made and broken duringeach revolution of the generator shaft 58. Since the cup 44, in whichthe mercury is contained, is electrically connected to one of theterminals of the primary winding of the transformer 20, the interrupterl1 will make and break the circuit in the primary winding of thetransformer once during each revolution of the generator shaft 56. Theinterrupter preferably is arranged to make and break the circuit quicklywith a relatively long period of interrupted circuit.

Referring now to Figs. noted that the casing 22 in which the transformer20 is mounted comprises a front wall 68 which is shaped conveniently tocoincide withthe curvature of the back of the automobile body 24. Theupper and lower horizontal walls of the casing are substantiallyrectangular. The removable rear wall 86 of the casing is provided withforwardly extending flanges which overlie and engage the rear edgeportions of the horizontal walls 62 and 84. The rear wall it is providedwith an opening over which is mounted a transparent cover member 68through which light from the signal light 10 of the present invention,preferably a neon tube, is visible. The transformer 20 is mounted onsuitable brackets 12 which are secured to the forward surface of a 5, 6,and 7, itwillbe substantially vertical partition plate 14 which issecured removably in positi'in within the casing in any suitable manner.Conductors 16 and 18 forming the terminals of the high tension secondarywinding of the transformer 20 are electrically connected to bindingposts 88 and 82 respectively which extend through the partition plate14. On the other side of the partition plate 14 and electricallyconnected to the binding posts and 82 are contact members 84 and 86 inthe form of spring clips which are arranged to receive the electrodeterminals 88, '90 .of the neon tube 10. It is evident from the abovethat the transformer 20 and the neon light 18 are rigidly fixed to thebody of the motor vehicle and replacement of broken and defective parts.

With the above arrangement, .each current pulse in the low tensionprimary winding of the transformer produces a high voltage pulse in thehigh tension secondary winding and results in a momentary flash orillumination of the neon tube. When the engine I0 is idling, the currentpulses in the transformer primary occur at low frequency and hence thereare relatively wide periods of time intervening between successiveilluminations of the neon tube. When, however, the engine speedincreases, and consequently the speed of the generator, the frequency ofenergizing impulses in the transformer correspondingly increases andhence the flashes of the neon tube correspondingly increase in'freqgencWhen the engine speed corresponds to a car speed of say, twenty milesper hour, the flashes are so frequent as to give the effect ofpractically continuous illumination. Thus speed changes of the car areindicated as well as the stationary condition thereof when the engine isidling.

Referring now to Figs. 3 and 4, of the drawings, an alternating orpulsating current generator 92 is operatively connected to the shaft 56of the engine-driven generator I2 or is otherwise driven by the engineat a speed proportional therewith. The generator '92 is provided with astationary stator 93 having a winding 94 and a rotor 95 which ispermanently magnetized and rotated by the engine. With the generator 92as illustrated, there will be two current pulses for each completerotation of the rotor. These impulses, through leads 90 and 98, energizethe low tension winding of a transformer I00, the high tension windingof which is connected to the neon tube I02. Since the speed of thegenerator is proportional to the engine speed, the fiashings of the neontube will be slow at slow engine speed and faster for faster enginespeeds and hence the change of car speed, at low speeds can bedetermined by observing the change of frequency of the neon tube flashesas with the first modification hereinbefore described. Preferably thedesign of the generator 92 and its speed relation with the engine speedis such that the successive flashes of the signal light can be observedreadily when the car speed is less than some predetermined rate as, saytwenty miles per hour.

Referring now to Fig. 12, the terminals of the primary winding of thetransformer I are designated as I04 and I06 respectively. Thetransformer I00 is mounted on a base I08 and is enclosed by a casing IIO(Fig. 11) the rear wall of which is provided with an opening to receivea transparent sheet II z'through which a flat neon tube I I0 is visible.The neon tube I I4 is mounted in contact members H6, H8 which engageterminal electrodes I20, and I22 respectively, fixed to the ends of theneon tube I I4. As shown bestin Figs. 8, 9, and the neon tube H4 isrectangularly shaped and has substantial vertical height. The chamberwithin the tube II4 has a volume per unit length which is substantiallythe same as the volume per unit length of the neon tube I0 shown in Fig.7. Thus, by'the use of this wide flat tube a substantial area is lightedand the rear wall and its transparent sheet II2 if desired may be of anydesired configuration to provide some illuminated symbol in addition toproviding a warning illumination.

Both of the modifications shown in Figs. 1 and 2, and 3 operate insubstantially the same manner. When the car engine is idling, theinterval between successive energizing pulses to the signal light isrelatively long and hence the intervals between successive flashes ofthe light are correspondingly long and the separate flashes are readilyapparent. When the speed of the motor increases, the frequency of theflashes or energizations of the neon lamp increases and when the vehiclereaches an appropriate speed the frequency of the energizations is sogreat that the neon lamp appears to be continuously lighted. When thevehicle is slowed down sufliciently, the frequency of the energizationsof the neon lamp decreases to a point where the periodic lighting of theneon lamp is vibile to the observer and I if the motor vehicle furtherslows down the frequency of the energizations of the neon lamp furtherdecreases to a point where the successive flashes of the neon lamp occurat relatively long intervals. Thus, the operator of the following car isenabled instantly to determine whether or not the leading car isincreasing or decreasing its speed and these indications of increase ordecrease of speed of the leading car is entirely independent of anycontrol by the operator of the vehicle. A stationary car with enginerunning is also made known by the slow flashing of the signal light.

A gaseous conduction tube with cold electrodes, herein represented as aneon tube is preferred as a signal light because it is conducting onlyat a definite elevated threshold voltage so that it has a sharp startand stop of illumination, and can accommodate itself to a large voltagerange above the threshold voltage. It also has no fragile parts to breakunder vibration and requires but little power- Energization of the tubefrom a low voltage source through a transformer at the tube simplifiesthe wiring and the insulation thereof.

Operation of the tube under control of engine speed, in addition toindicating car-speed changes, also provides for the desirable indicationof a temporary starting condition of the car.

One of the requisites of this invention is that I the separate flashesof the signal light be discernable up to a substantial car speed. Hencethe length of time between flashes should be greater than the length oftime that the sensation of light persists with the average observer, forthe separate flashes to be readily observed below such car speed. Tothis end the energize.- tion pulse formulating means (circuitinterrupter II, generator 92) is operated at sufllciently slow speed toprovide visually separate flashes of the signal light up to the enginespeed corresponding to the predetermined car speed. The predeterminedcar speed is selected as one below which it is probable that some changein operation of the car i intended.

Having thus described my invention, what I claim as new and desire tosecure by Letters Patent of the United States is:

In a motor vehicle having an engine for propelling the vehicle, a neonwarning lamp, a transformer at the lamp having its high tensionsecondary winding connected to the lamp, 9. low

tension generator remote from the lamp and transformer and rotated bythe engine, low tension leads extended from'the generator and connectedto the low tension primary winding of the transformer, said generatorbeing an alternating current generator initiating separated currentpulses for energizing said transformer and illuminating said lamp, andmeans providing relative speeds of the engine and generator such thatthe lamp appears to glow steadily when the vehicle is travelling above apredetermined speed and visually distinct flashes of illuminations ofsaid lamp are apparent at vehicle speeds below said predetermined speed.

JOHN JOYCE.

